Liquid level sensor for liquid receptacle

ABSTRACT

Disclosed herein are various techniques and devices for detecting a level of fluid within a fluid collection receptacle. In one embodiment, a pressure sensor connected to a bottle is provided. The pressure sensor detects air pressure in the bottle as the bottle is filled with a liquid and provides information to determine a volume of the liquid in the bottle.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of claims the benefit of U.S. Pat.No. 11,433,166, filed on Apr. 29, 2019, which in claims the benefit andpriority of U.S. Provisional Application No. 62/663,719, filed Apr. 27,2018, which are both incorporated herein by reference in theirrespective entireties, including but not limited to those portions thatspecifically appear hereinafter, the incorporation by reference beingmade with the following exception: In the event that any portion of theabove-referenced patent and provisional application is inconsistent withthis application, this application supersedes said above-referencedpatent and provisional application.

BACKGROUND 1. Technical Field

This disclosure relates generally to a liquid level sensor for detectingan amount of liquid in a liquid receptacle. In one embodiment, a liquidlevel sensor may obtain sensor data by detecting a level of milk in amilk bottle and using that sensor data to determine an amount of milk orvolume of milk within the bottle. Sensors may be disposed within thereceptacle and continuously monitor a liquid level within the receptacleand provide updated sensor data reflecting an increased liquid level.

2. Description of the Related Art

Receptacles for fluid storage and collection have existed sinceantiquity. More recently, some receptacles have been marked withgraduated measurement indicators. Beakers, metal jars, measuring cups,pitchers, and a host of other fluid storage and collection receptacleshave been marked with graduated measurement indicators to show how muchfluid is contained within the receptacle. The graduated measurementindicators may be marked on the fluid storage and collection receptaclesbased on mathematical volumetric calculations to accurately reflect anamount of fluid within the fluid storage and collection receptacles. Inother words, various indicators may be marked on the side of a fluidstorage and collection receptacle to accurately measure a fluid levelwithin the receptacle. For example, the receptacle may includeindicators that show one ounce, two ounces, three ounces, etc., whichwhen compared to a fluid level within the receptacle shows a person howmuch liquid, in fluidic measurements, is contained within thereceptacle.

While these graduated indicators are helpful, their usefulness issomewhat limited. For example, in fluid collection receptacles,graduated indicators provide no indication of flow rate, e.g., how muchfluid is collected per time unit. In situations where fluid collectionis a slow process, a person may lose interest or be unable to monitor aflow rate due to the amount of time necessary to obtain a flow rate.Another weakness of graduated indicators is that graduated indicatorsare only helpful if the receptacle is in an area where it can be easilyseen by a person. Thus, in applications where the fluid collectionreceptacle is hidden or not readily visually accessible, graduatedindicators provide a person with no useful information about the volumeof liquid collected within the collection receptacle.

One specific situation where graduated indicators are of limitedusefulness is in nursing an infant or breast pumping. Typical breastpumps include a bottle that collects milk as it is pumped. However, inmany situations, it may be inconvenient for a mother to access a bottleduring pumping. For example, since a bottle is usually connected to abreast pump which is, in turn, connected to the mother's breast, it maybe difficult for a mother to accurately see how much milk has beencollected within the milk receptacle. Similarly, when a mother ispumping from both breasts, it may be difficult for a mother toaccurately assess how much milk has been produced over a certain amountof time from each breast using nothing more than graduated indicatorsand a stopwatch.

It is therefore one object of this disclosure to provide a flow ratesensor system and apparatus. It is a further object of this disclosureto provide a fluid receptacle that includes one or more sensorsinstalled within the receptacle. Another object of this disclosure is toprovide a sensor to sense a fluid level within a fluid receptacle and tosense a flow rate for fluid entering the receptacle. Another object ofthis disclosure is to provide a fluid receptacle which contains one ormore sensors to accurately sense a fluid level within the fluidreceptacle and sense a flow rate for milk entering the receptacle.

SUMMARY

Disclosed herein is a pressure sensor connected to a bottle. Thepressure sensor detects air pressure in the bottle as the bottle isfilled with a liquid and provides information to determine a volume ofthe liquid in the bottle.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate one or more embodiments of a fluidcollection receptacle within which is installed one or more sensors foraccurately assessing both a flow rate and amount of milk containedwithin the fluid collection receptacle.

FIG. 1 illustrates a fluid collection receptacle including one or moresensors.

FIG. 2 illustrates a top for a fluid collection receptacle including asensor.

FIG. 3 illustrates a sensor configuration for a fluid collectionreceptacle which avoids false readings due to fluid droplets runningdown an inside portion of the fluid collection receptacle.

FIG. 4 illustrates an alternative sensor configuration for a fluidcollection receptacle which avoids false readings due to fluid dropletsrunning down an inside portion of the fluid collection receptacle.

FIG. 5 a illustrates a sensor which may be installed within a fluidcollection receptacle.

FIG. 5 b illustrates another sensor which may be installed within afluid collection receptacle.

FIG. 5 c illustrates another sensor which may be installed within afluid collection receptacle.

FIG. 5 d illustrates another sensor which may be installed within afluid collection receptacle.

FIG. 6 illustrates a fluid collection receptacle in which sensorelements are attached to a sensor within abase portion of the fluidcollection receptacle.

FIG. 7 illustrates a fluid collection receptacle in which sensorelements are disposed within the fluid collection receptacle.

FIG. 8 illustrates a fluid collection receptacle in which sensorelements are disposed on a rod disposed within the fluid collectionreceptacle.

FIG. 9 illustrates an alternative implementation of a fluid collectionreceptacle in which sensor elements are disposed on a rod disposedwithin the fluid collection receptacle.

FIG. 10 illustrates a fluid collection receptacle in which a rod may beinstalled from a bottom portion of the fluid collection receptacle.

FIG. 11 illustrates a fluid collection receptacle which mates with asealed housing containing a capacitive or inductive rod which may beinstalled on a top of the fluid collection receptacle.

FIG. 12 illustrates a fluid collection receptacle 1200 which contains ahousing and one or more strain gauges disposed between the housing andan inner receptacle.

FIG. 13 illustrates a fluid collection receptacle which contains ahousing and a strain gauge.

FIG. 14 illustrates a fluid collection receptacle which implements asiphoning system.

FIG. 15A illustrates an exemplary implementation of a fluid collectionreceptacle which uses a circuit which includes an inductive coil wrappedcircumferentially around the fluid collection receptacle.

FIG. 15 b illustrates another exemplary circuit which may be used toidentify an absolute voltage through an inductor coil.

FIG. 16 illustrates an exploded view of a fluid collection receptaclethat implements a pressure sensor with a rigid tube to track pressurechanges and determine a volume of fluid within the fluid collectionreceptacle.

FIG. 17 illustrates an assembled view of the fluid collection receptacleshown in FIG. 16 .

FIG. 18 illustrates an exploded view of another embodiment of a fluidcollection receptacle that implements a pressure sensor with a rigidtube to track pressure changes and determine a volume of a fluid withinthe fluid collection receptacle.

FIG. 19 illustrates an assembled view of the fluid collection receptacleshown in FIG. 18 .

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

In the following description, for purposes of explanation and notlimitation, specific techniques and embodiments are set forth, such asparticular techniques and configurations, in order to provide a thoroughunderstanding of the device disclosed herein. While the techniques andembodiments will primarily be described in context with the accompanyingdrawings, those skilled in the art will further appreciate that thetechniques and embodiments may also be practiced in other similardevices.

Reference will now be made in detail to the exemplary embodiments,examples of which are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers are used throughout the drawings torefer to the same or like parts. It is further noted that elementsdisclosed with respect to particular embodiments are not restricted toonly those embodiments in which they are described. For example, anelement described in reference to one embodiment or figure, may bealternatively included in another embodiment or figure regardless ofwhether or not those elements are shown or described in anotherembodiment or figure. In other words, elements in the figures may beinterchangeable between various embodiments disclosed herein, whethershown or not.

FIG. 1 illustrates a fluid collection receptacle 100 including one ormore of sensor 115 a and sensor 115 b. Fluid collection receptacle 100may be implemented as a bottle for collecting milk via a breast pump. Inone embodiment, milk may be collected within fluid collection receptacle100 via opening 105. Opening 105 of fluid collection receptacle 100 maybe encompassed by a collar 110 which allows fluid collection receptacle100 to mate with or screw into another element, such as a breast pump.Fluid collection receptacle 100 includes one or more sensors, such assensor 115 a and sensor 115 b. Sensor 115 a may be implemented singly orin combination with sensor 115 b and vice versa. Sensor 115 a and/orsensor 115 b may be disposed along collar 110 of fluid collectionreceptacle 100, as shown in FIG. 1 . However, sensor 115 a and sensor115 b may be positioned along a top portion of fluid collectionreceptacle 100. More specifically, sensor 115 a and sensor 115 b may bepositioned anywhere fluid collection receptacle side 125 a or fluidcollection receptacle side 125 b meet collar 110.

Sensor 115 a being positioned along or about collar 110 provides afield-of-view for sensor 115 a of fluid collection receptacle side 125 awithin sensing cone 120 a. Similarly, sensor 115 b being positionedalong or about collar 110 provides a field-of-view for sensor 115 b offluid collection receptacle side 125 b within sensing cone 120 b. Sensor115 a and/or sensor 115 b, depending on specific configuration, may emita beam of light substantially parallel to fluid collection receptacleside 125 a and/or fluid collection receptacle side 125 b, respectively.Sensor 115 a may further receive a reflection of a beam of light withinsensing cone 120 a. Similarly, sensor 115 b may receive a reflection ofa beam of light within sensing cone 120 b.

Sensor 115 a and sensor 115 b may be implemented as “time-of-flight”sensors. In other words, sensor 115 a and sensor 115 b may be used todetermine an amount of time between when a beam of light is emitted andwhen a reflection of the beam of light is detected. By simplecalculation using the known constant for the speed of light, a computerprocessor associated with sensor 115 a and sensor 115 b may determine adistance between sensor 115 a and sensor 115 b and a level of liquidcollected within fluid collection receptacle 100. Accordingly, as liquidcollects within fluid collection receptacle 100 sensor 115 a and sensor115 b may constantly monitor a level of rising fluid within fluidcollection receptacle 100. For example, as milk is collected during abreast pumping session, sensor 115 a and sensor 115 b may be used todetermine a liquid level of milk contained within fluid collectionreceptacle 100 by a computer processor associated with sensor 115 a andsensor 115 b. Further, the computer processor associated with sensor 115a and sensor 115 b may use a known volume of fluid collection receptacle100 to calculate flow rate for liquid entering fluid collectionreceptacle 100 and a volume of liquid contained within fluid collectionreceptacle 100.

In some situations, sensor 115 a may be adequate to determine a liquidlevel of fluid contained within fluid collection receptacle 100.However, sensor 115 b may be useful in other situations, such as whenfluid collection receptacle 100 is not level or a surface of the fluidcontained within fluid collection receptacle 100 is not horizontal. Toensure accurate measurement of a liquid level, a volume, a flow rate, orother measurement, fluid collection receptacle 100 may, in somesituations, be implemented with an accelerometer to measure tilt angles.

FIG. 2 illustrates a top 200 for a fluid collection receptacle, such asfluid collection receptacle 100 shown in FIG. 1 , including a sensor230, as will be discussed below. Fluid collection receptacle 100, forexample, may connect with top 200 which, in turn, may connect to otherelements of a breast pump. Top 200 may be disposed in a housing 205which may be generally cylindrical. It is noted that housing 205 may beimplemented in any sufficient shape. Housing 205 includes an opening 210through which milk, for example, may drain from a breast pump intohousing 205. The milk, in this example, may land on an inclined plane215 which funnels milk to a spout 220. Spout 220 meters milk intodroplets of substantially uniform size.

Housing 205 may further include a side portion 225 in which a sensor 230is disposed. Sensor 230 may also be implemented as a time-of-flightsensor which includes a field-of-view of the milk droplets released fromspout 220 through sensing cone 235 of sensor 230. As droplets arereleased from spout 220 and pass through sensing cone 235, sensor 230may detect a number of uniform droplets and calculate an overall volumefor milk that has been released from spout 220. One advantage of top 200is that regardless of an angle of tilt of top 200, up to approximately45°, a droplet of milk released from spout 220 will pass through sensingcone 235 of sensor 230. In this manner, an accurate measurement of avolume of liquid collected within a fluid collection receptacle, such asfluid collection receptacle 100 shown in FIG. 1 , may be determined.

FIG. 3 illustrates a sensor configuration for a fluid collectionreceptacle 300 that avoids false readings due to fluid droplets runningdown an inside portion of fluid collection receptacle 300. Fluidcollection receptacle 300 may include an opening 305 through which milkis drained from a breast pump. In some circumstances, milk that isdrained from the breast pump may flow down a side of opening 305 whichmay result in a quantity of milk not being accurately detected betweenemitter 310 a and detector 310 b. Accordingly, as shown in FIG. 3 ,opening 305 may be expanded outwardly along fluid collection receptacleedges 315 a and 315 b. This outward expansion of opening 305 along edges315 a and 315 b increases a first diameter 320 of opening 305 to asecond diameter 325 where the first diameter 320 is less than the seconddiameter 325. In other words, because of the outward expansion of edges315 a and 315 b, a milk droplet stuck to the side of opening 305 mustdrop when the milk droplet encounters edges 315 a and 315 b.

Accordingly, any milk that has been drained through opening 305 from thebreast pump may be formed in droplets by at least a top of edges 315 aand 315 b. In this manner, droplets may be detected between emitter 330a and detector 330 b as the droplets fall into a collection portion 335of fluid collection receptacle 300. In one embodiment, a computerprocessor associated with the breast pump may compare the number ofdroplets detected between emitter 310 a and detector 310 b with thenumber of droplets detected between emitter 330 a and detector 330 b todetermine an overall flow rate of milk, or other fluid, as the milk iscollected within collection portion 335 of fluid collection receptacle300.

FIG. 4 illustrates an alternative sensor configuration for a fluidcollection receptacle 400 that avoids false readings due to fluiddroplets running down an inside portion of the fluid collectionreceptacle. Fluid collection receptacle 400 may include an opening 405through which milk is drained from a breast pump. In some circumstances,milk that is drained from the breast pump may drain down a side ofopening 405 which may result in a quantity of milk not being accuratelydetected between emitter 410 a and detector 410 b. Accordingly, as shownin FIG. 4 , opening 405 may be expanded outwardly, at right angles toopening 405 by collection receptacle edges 415 a and 415 b creating adefined break between opening 405 and collection portion 435 of fluidcollection receptacle 400. This outward expansion of opening 405 alongedges 415 a and 415 b increases a first diameter 420 of opening 405 to asecond diameter 425 where the first diameter 420 is less than the seconddiameter 425. In other words, because of the outward expansion of edges415 a and 415 b, a milk droplet stuck to the side of opening 405 mustdrop when the milk droplet encounters edges 415 a and 415 b.

Accordingly, any milk that has been drained through opening 405 from thebreast pump may be formed in droplets by at least a top of edges 415 aand 415 b. In this manner, droplets may be detected between emitter 430a and detector 430 b as the droplets fall into a collection portion 435of fluid collection receptacle 400. In one embodiment, a computerprocessor associated with the breast pump may compare a number ofdroplets detected between emitter 410 a and detector 410 b with a numberof droplets detected between emitter 430 a and detector 430 b todetermine an overall flow rate of milk, or other fluid, as the milk iscollected within collection portion 435 of fluid collection receptacle400.

FIG. 5A illustrates a sensor 500 which may be installed within a fluidcollection receptacle. Sensor 500 operates as a capacitive sensor. Forexample, the capacitance of sensor 500 may be proportional due todielectric variation caused by a changing volume of liquid inside acontainer, such as a fluid collection receptacle. In this manner sensor500 may be installed within a portion of a fluid collection receptacle,such as those disclosed herein. Sensor 500 may be disposed on an insidesurface of a fluid collection receptacle, may be disposed within a wallof a fluid collection receptacle, or may be disposed on an outsidesurface of a fluid collection receptacle.

As shown in FIG. 5A, sensor 500 includes a conductive trace 505 whichconnects fingers 505 a-505 g. Finger 505 g may be disposed at a bottomof a fluid collection receptacle while finger 505 a may be disposed at atop of a fluid collection receptacle. As a fluid, such as milk, iscollected within a fluid collection receptacle the level of milkproceeds up from finger 505 g towards finger 505 a. Further, as thefluid level increases, or raises, within a fluid collection receptacle acapacitance within sensor 500 changes proportionally to the increase ofthe fluid level. A computer processor associated with a breast pump maydetect these proportional changes in the capacitance of sensor 500 as alevel of fluid increases within the fluid collection receptacle. Thecapacitance may be detected and correlated with an overall volume offluid contained within the fluid collection receptacle.

FIG. 5B illustrates a sensor 500 which may be installed within a fluidcollection receptacle. In FIG. 5B, sensor 500 is implemented in asymmetric interlaced fashion. As before with respect to FIG. 5A, aconductive trace 510 is connected to a plurality of fingers 510 a-510 g.To increase capacitive resolution and minimize crosstalk between fingers505 a-505 g shown in FIG. 5A, a second conductive trace 515 is providedwith fingers 515 a-515 g which are installed in the fluid collectionreceptacle. In this embodiment, for example, finger 510 a is separatedfrom finger 510 b by finger 515 b, and so on providing an interlacedrelation between fingers 510 a-510 g and fingers 515 a-515 g, as shownin FIG. 5B.

FIG. 5C illustrates a sensor 500 which may be installed within a fluidcollection receptacle. In FIG. 5C, sensor 500 is implemented in anasymmetric interlaced fashion. As before with respect to FIG. 5B, aconductive trace 520 includes fingers 520 a-520 e while conductive trace525 includes fingers 525 a-525 e. However, fingers 525 a-525 e arenarrower in terms of width than fingers 520 a-520 e to provide a desiredcapacitive resolution. In other words, fingers 520 a-520 e individuallyoccupy a greater area than any one of fingers 525 a-525 e. Variations intotal area between sets of fingers 520 a-520 e and fingers 525 a-525 eadjust a relative amount of capacitance within sensor 500 which, inturn, adjusts a resolution of sensor 500 to accurately detect a fluidlevel within a fluid collection receptacle.

FIG. 5D illustrates a sensor 500 to be installed within a fluidcollection receptacle. Sensor 500 of FIG. 5D is an alternative exampleof an offset or skewed asymmetric interlaced sensor. Sensor 500 includesa conductive trace 530 which is connected to fingers 530 a-530 g and aconductive trace 535 which is connected to fingers 535 a-535 f. Fingers535 a-535 f, however, not only have a smaller area than fingers 530a-530 g but also are skewed closer to a finger below than to a fingerabove a particular finger. In other words, finger 535 a is skewed closerto finger 530 a, while finger 535 b is skewed closer to finger 530 b,and so on. Skewing distances between fingers 530 a-530 g and fingers 535a-535 f adjusts a relative amount of capacitance between fingers 530a-530 g and fingers 535 a-535 f in sensor 500 which, in turn, adjuststhe resolution of sensor 500 to accurately detect a fluid level within afluid collection receptacle using sensor 500.

FIG. 6 illustrates a fluid collection receptacle 600 in which sensorelement 610 and sensor element 615 are attached to a sensor 630 within abase portion 620 of fluid collection receptacle 600. Fluid collectionreceptacle 600 may be implemented as bottle 605. Bottle 605 includes anopening 605 a through which milk, for example, may pass and be containedwithin bottle 605. Bottle 605 may be encompassed by a side 605 b whichdefines a circumference of bottle 605. Bottle 605 includes, built withinside 605 b, a first sensor element 610 and a second sensor element 615.First sensor element 610 and second sensor element 615 are disposedwithin a wall of bottle 605 defined by side 605 b. For example, bottle605 may be constructed using plastic materials and first sensor element610 and second sensor element 615 may be positioned within or containedwithin the plastic materials. Alternatively, first sensor element 610and second sensor element 615 may be positioned on an inner or outersurface of side 605B.

First sensor element 610 may include one or more fingers 610 a-610 dwhile second sensor element 615 may include one or more fingers 615a-615 e. First sensor element 610 may extend one or more fingers 610a-610 d circumferentially down around bottle 605, as shown. Similarly,second sensor element 615 may extend one or more fingers 615 a-615 ecircumferentially up around bottle 605. First sensor element 610 andsecond sensor element 615 may be implemented using any electricallyconductive material. For example, first sensor element 610 and secondsensor element 615 may be implemented using a metal such as copperarranged in thin sheets and cut into symmetric combs with symmetricinterlacing fingers as shown in FIG. 6 . In another embodiment firstsensor element 610 and second sensor element 615 may be implementedusing a conductive ink disposed within bottle 605 into symmetric combswith interlacing fingers as shown in FIG. 6 .

Fingers 610 a-610 d are shown in FIG. 6 in a symmetric interlacedconfiguration with fingers 615 a-615 e. That is, for example, finger 610a is symmetrically disposed between finger 615 a and finger 615 b. It isnoted that other configurations are possible. For example, fingers 610a-610 d and 615 a-615 e may be implemented in an asymmetric interlacedconfiguration or in an offset asymmetric configuration, as discussedabove. So long as fingers 610 a-610 d and 615 a-615 e are substantiallyequal in terms of area, mass, and density, any combination of fingers610 a-610 d and 615 a-615 e which extends vertically along a verticalaxis defined by bottle 600, first sensor element 610 and second sensorelement 615 may be implemented in any configuration.

Bottle 600 may include a base portion 620 which may be attached tobottle 600 using any technique known in the art. In FIG. 6 , baseportion 620 is shown with attachment 625 a and attachment 625 b.Attachment 625 a and attachment 625 b are simply friction fittings thatsecure base portion 620 to bottle 600 by friction connection. Baseportion 620 further includes a sensor 630 which electrically connects tofirst sensor element 610 and second sensor element 615. In this manner,sensor 630 may detect a relative amount of capacitance between firstsensor element 610 and second sensor element 615. Sensor 630 may thentransmit information about the relative amount of capacitance betweenfirst sensor element 610 and second sensor element 615 to a computerprocessor associated with the breast pump. This computer processor may,based on this information, determine a level of milk, for example,within bottle 600. The computer processor may, based on thisinformation, further determine a volume of milk, for example, withinbottle 600. The computer processor may also, based on this information,detect a flow rate for milk, for example, entering bottle 600.

FIG. 7 illustrates a fluid collection receptacle 700 in which sensorelements 705 a-705 d are disposed within fluid collection receptacle700. In this embodiment, sensor elements 705 a-705 d may besilk-screened onto a surface of fluid collection receptacle 700 usingconductive inks or other conductive materials. It should be noted thatsensor elements 705 a-705 d may be installed on an outside surface offluid collection receptacle 700, an inside surface of fluid collectionreceptacle 700, or between an inside and outside surface of fluidcollection receptacle 700. Sensor elements 705 a-705 d may also beinjection molded onto the bottle via comolding or overmolding of aconductive plastic material onto an insulating plastic material, forexample. In another embodiment, sensor elements 705 a-705 d may beseparable from the bottle by being installed within a sleeve that may bedisposed around the outside surface of fluid collection receptacle 700.

In this manner, sensor elements 705 a and 705 b may be disposed on afirst surface, such as a front surface, of a fluid collection receptacle700 while sensor elements 705 c and 705 d may be disposed on a secondsurface, such as a side surface of fluid collection receptacle 700. Forexample, sensor elements 705 a and 705 b may form a first pair of sensorelements which may be disposed at approximately 90° from sensor elements705 c and 705 d which may form a second pair of sensor elements. In thismanner, sensor elements 705 a-705 d may sense an amount of fluid withinfluid collection receptacle 700 even when fluid collection receptacle700 is tilted in a left/right direction and a front/back direction.

FIG. 8 illustrates a fluid collection receptacle 800 in which sensorelements 805 a and 805 b are disposed on a rod 810 disposed within fluidcollection receptacle 800. Rod 810 may be formed to rise from a bottomportion of fluid collection receptacle 800 using the same material usedfor fluid collection receptacle 800 (e.g., plastic). Rod 810 may includesensor elements 805 a and 805 b which are similar in implementation, inthis example, to sensor 500 shown in FIG. 5B using an interlacedsymmetric pattern (although any of sensors 500 shown in FIGS. 5A-5D maybe used on rod 810). Other shapes for sensor elements 805 a and 805 bare possible in any of the embodiments disclosed herein. For example,sensor elements 805 a and 805 b may be implemented as a series ofchevrons, zig-zags, vertical lines, horizontal lines, diagonal lines,circular lines about the circumference of fluid collection receptacle800 or other implementations. Rod 810 may or may not be hollow along aninside portion of rod 810. In this manner, sensor elements 805 a and 805b may be disposed on an outside surface of rod 810, an inside surface ofrod 810 or may be disposed between an inside and outside surface of rod810 within the materials that form fluid collection receptacle 800.

In one embodiment, sensor elements 805 a and 805 b may be printed usingconductive ink, such as silver ink, on, within, or along an insidesurface of rod 810. Alternatively, sensor elements 805 a and 805 b maybe implemented using a flexible PCB (printed circuit board) that may befitted on, in, or outside rod 810. Fluid collection receptacle 800 mayfurther include leads which may allow various electronic componentsassociated with sensor elements 805 a and 805 b which are accessiblesuch that electronics may be connected to sensor elements 805 a and 805b while still being able to come into electrical contact with sensorelements 805 a and 805 b and while not coming in contact with fluidwithin fluid collection receptacle 800.

FIG. 9 illustrates an alternative implementation of a fluid collectionreceptacle 900 in which sensor elements 905 a-905 d are disposed on arod 910 disposed within fluid collection receptacle 900. Rod 910 may beformed to rise from a bottom portion of fluid collection receptacle 900using the same material used for fluid collection receptacle 900 (e.g.,plastic). Rod 910 may include sensor elements 905 a-905 d which aresimilar in implementation, in this example, to sensor 700 shown in FIG.7 . In FIG. 9 , however, rod 910 is shown as being implemented as asquare or a rectangular shape, which provides two separate axes forsensing fluid level, as discussed above in FIG. 7 . For example, sensorelements 905 a and 905 b may be formed as a first parallel pair ofsensor elements and may be disposed at 90° to sensor elements 905 c and905 d, which form a second parallel pair of sensor elements. Such aconfiguration allows a liquid level within fluid collection receptacle900 to be sensed regardless of whether fluid collection receptacle 900is tilted to the left/right or forwards/backwards.

Rod 910 may be hollow along an inside portion of rod 910. In thismanner, sensor elements 905 a-905 d may be disposed on an outsidesurface of rod 910, an inside surface of rod 910 or may be disposedbetween an inside and outside surface of rod 910 within the materialsthat form fluid collection receptacle 900. Regardless, rod 910 may beseparated from direct contact with milk contained within fluidcollection receptacle 900.

FIG. 10 illustrates a fluid collection receptacle 1000 in which a rod1005 may be installed from a bottom portion 1010 of fluid collectionreceptacle 1000. Fluid collection receptacle 1000 may include a holecorresponding to the size and shape of rod 1005. Rod 1005 may thereforebe inserted into a hole disposed within bottom portion 1010 of fluidcollection receptacle 1000 and installed by any connection mechanismbetween rod 1005 and bottom portion 1010 of fluid collection receptacle1000. For example, fluid collection receptacle 1000 may include threadsinto which rod 1005 may be inserted and to which rod 1010 may beconnected. Bottom portion 1010 may further include a PCB (printedcircuit board) with batteries that may operate the PCB and one or moresensor elements installed in rod 1005. Bottom portion may be threadedonto fluid collection receptacle 1000 and fully sealed for sanitizing.

In one embodiment, a straw 1015 may be installed around rod 1005 toprotect milk within fluid collection receptacle 1000 from coming incontact with rod 1005. Straw 1015 may be constructed so as to create abarrier between milk and sensor elements (such as any of the sensorelements disclosed herein) that may be installed on rod 1005 and whichcannot be sanitized to a sufficient degree.

Bottom portion 1010 may further include a tilt sensor which identifieswhen fluid collection receptacle 1000 is tilted away from vertical, orat least far enough away from vertical that the angle of tilt is outsidea predetermined threshold of tilt. Bottom portion 1010 may furtherinclude a gimbal, or control a gimbal disposed within a breast pump toredirect milkflow during such times as the angle of tilt for fluidcollection receptacle 1000 is outside a predetermined level.

FIG. 11 illustrates a fluid collection receptacle 1100 which mates witha sealed housing 1105 containing a capacitive or inductive rod 1110which may be installed on a top of fluid collection receptacle 1100. Inthis embodiment, rod 1110 may include sensor elements, such as thosedisclosed herein, and may be installed at a center of housing 1105 thatmates with fluid collection receptacle 1100. Rod 1110 may be sealedwithin housing 1105 which permits capacitive or inductive coupling toone or more electronic or processing elements. Since housing 1105 androd 1110 are sealed by a layer of plastic or silicone, housing 1105 androd 1110 do not directly come into contact with milk contained withinfluid collection receptacle 1100. Further, housing 1105 and rod 1110 maybe washed by a dishwasher because they are sealed.

In one embodiment, a capacitive sensor element installed on rod 1110 maybe implemented as one or more rungs which are disposed side by sidealong a central ground. One advantage of this implementation is that thecapacitive sensor elements may be installed by printing with conductiveink, such as silver ink, which may allow for a better resolution (e.g.,accuracy in determining an amount of liquid contained within fluidcollection receptacle 1100).

Other measurements for an amount of milk contained within a fluidcollection receptacle, such as those fluid collection receptaclesdisclosed herein. For example, since the specific density of breast milkis relatively consistent between different people (or may be ascertainedfor each individual), weight may also be an indicator of volume or maybe a separate measurement that may be useful. For example, a scale thatmay be tared for a weight of a fluid collection receptacle (the totalweight of the fluid collection receptacle and the milk contained insideminus the predetermined weight of the fluid collection receptacle) maybe integrated into a carrying case for the breast pump system. Thebreast pump system may receive weight information from the scale andvolume may be extrapolated and automatically recorded in a memory of adevice associated with the breast pump system. In anotherimplementation, a three-dimensional touch system, a force gauge, or acapacitive screen on a smartphone may be used to measure a weight ofbottles when a breast pumping session has terminated. The smartphone,for example, may automatically record a weight of the bottle (tared forthe weight of the bottle) and extrapolate a total volume of milkcontained within the bottle.

Another implementation, shown in FIG. 12 , illustrates a fluidcollection receptacle 1200 which contains a housing 1205 and one or morestrain gauges 1210 disposed between housing 1205 and an inner receptacle1215. One advantage of fluid collection receptacle 1200 is that straingauges may measure the weight of the milk within inner receptacle 1215while a breast pump is being worn. Further, the inner reservoir mayensure that milk is fully contained within fluid collection receptacle1200 and isolates any milk that may spill from contacting the user'sbody or clothes.

FIG. 13 illustrates a fluid collection receptacle 1300 which contains ahousing 1305 and a strain gauge 1310. Strain gauge 1310 may connecthousing 1305 to inner receptacle 1315. Inner receptacle 1315 may receivebreast milk as it is expressed. As milk aggregates within innerreceptacle 1315, strain gauge 1310 may record a weight increase causedby the addition of milk to inner receptacle 1315. In one embodiment,strain gauge 1310 may be disposed under a cantilever 1320 whichamplifies the weight of milk in the inner receptacle and providesadditional resolution to the weight measurement. In another embodiment,an accelerometer (not shown) may be installed within fluid collectionreceptacle 1300 to find a force component in the direction of gravity toincrease the accuracy of the weight measurement obtained via straingauge 1310.

Fluid collection receptacle 1300, and the other fluid collectionreceptacles disclosed herein, may include liquid-level sensors, such astime of flight sensors, capacitive sensors, ultrasonic sensors, opticalsensors, and other sensors, coupled to an accelerometer to compensatefor tilting while still determining an accurate volume or weight of milkcontained within inner receptacle 1315.

FIG. 14 illustrates a fluid collection receptacle 1400 which implementsa siphoning system. Fluid collection receptacle 1400 includes one ormore siphoning channels 1405 which may allow milk to aggregate to aparticular level in a first reservoir 1410 until it reaches a certainlevel 1415 and is drained into a second reservoir 1420 through a drain1425 by one or more vacuums 1430 disposed in the one or more siphoningchannels 1405. In this manner, as first reservoir 1410 fills with milk,it is subsequently drained into second reservoir 1420. However, sincethe volume of first reservoir 1410 is known, a mechanism disposed withinfluid collection receptacle 1400 (not shown) may count the number oftimes first reservoir 1410 is drained into second reservoir 1420 anddetermine a total volume of milk drained into and contained in secondreservoir 1420. Other siphoning mechanisms are contemplated. Forexample, a U-shaped siphon may be implemented instead of the inverted Ushaped siphon shown in FIG. 14 . Alternatively, a float siphon may beimplemented which floats up to a particular level at which a valve isopened and milk in first reservoir 1410 is allowed to drain into secondreservoir 1420.

Other systems may be used for determining a fluid level in a fluidcollection receptacle. For example, a camera of a smart phone may applydynamic filters on top of a computer image recognition software for aparticular fluid collection receptacle. Image recognition systems mayrecognize a particular bottle and dynamic filters may be overlaid inreal time on top of the bottle displayed on the screen. The filters maybe situated or manipulated by a user to demonstrate a volume level in abottle. Alternatively, the filters may automatically identify a volumelevel in a bottle and calculate a total volume of milk contained withina fluid collection receptacle.

Another implementation for detecting fluid flow may include a vibrationsensor or an optical sensor below a valve in a breast pump which detectsfluid flow.

Yet another implementation may be based on inductive flow sensing or, inother words, using a copper coil as a flow sensor and to determine atotal volume of expressed milk. FIG. 15A illustrates an exemplaryimplementation of a fluid collection receptacle 1500 which uses aninductive coil 1505 wrapped circumferentially around fluid collectionreceptacle 1500. Inductive coil 1505 may be installed on an outsidesurface of fluid collection receptacle 1500, an inside surface of fluidcollection receptacle 1500, between an outside surface of fluidcollection receptacle 1500 and an inside surface of fluid collectionreceptacle 1500 within fluid collection receptacle 1500. Alternatively,a sleeve may be installed around fluid collection receptacle 1500 whichprovides a removable coil disposed around fluid collection receptacle1500. Inductive coil 1505 is advantageous because it does not come intocontact with milk contained within fluid collection receptacle 1500 andmeasures a total volume of milk inside fluid collection receptacle 1500regardless of whether or not fluid collection receptacle 1500 is tilted.

As shown in FIG. 15A, a circuit is shown where resistor R1 is equal toresistor to R2 and an AC source is provided to prevent the inductance ofthe circuit from going to zero. Resistor R_(ref) may be tuned toresistor RL, Which corresponds to the resistance of inductive coil 1505when there is no milk within fluid collection receptacle 1500, such thatthe voltage V of the circuit is zero. As milk fills fluid collectionreceptacle 1500, voltage V changes. This change in voltage V may be usedto calculate a total amount of milk contained within fluid collectionreceptacle 1500.

In FIG. 15B, another exemplary circuit may be used which may be used toidentify an absolute voltage through an inductor coil. VL: may be avoltage across inductive coil 1505 while voltage VR may be a voltageacross the entire system (e.g., based on the total resistance across thesystem). As shown in FIG. 15B, the system may further include an ACsource. Unfortunately, a total voltage V cannot be determined by a voltmeter because the total voltage of the circuit has components of both VRand VL. However, because it is known that VL=−L di/dt, VR and VL may bedistinguished because VR and VL are 90° out of phase with each other.Because of this, an absolute voltage VL may be measured without a needto balance or tune inductive coil 1505 to resistor R_(ref), as discussedabove with respect to FIG. 15A.

Initially, however, there are some complications in adjusting forappropriate sensitivity for inductive coil 1505 and achieving theappropriate resolution for accurately determining an amount of milkwithin fluid collection receptacle 1500. Once VL is accuratelyidentified, VL may be amplified enough to measure a difference in thetotal inductance due to air and due to milk according to the followingequation:

L=N ² *pA/l

Where L is the total inductance of the circuit, N is the total number ofcoils wrapped around fluid collection receptacle 1500, p is a magneticconstant, A is a cross sectional area of fluid collection receptacle1500, and l is a total length of inductive coil 1505. It should also benoted that the magnetic constant p of milk is not equal to the magneticconstant p of air. Other implementations are possible that are based onthe phase between two different reference voltages. For example,reactance, and the ESR (equivalent series resistance) of a coil may beused to determine self-inductance with a relatively high accuracy.

FIG. 16 includes a fluid collection receptacle 1600 that implements apressure sensor 1605 with a rigid tube 1610 to track pressure changesand determine a volume of fluid within fluid collection receptacle 1600.Pressure sensor 1605 may detect air pressure inside rigid tube 1610,which may be enclosed by fluid within fluid collection receptacle 1600.As liquid fills rigid tube 1610, air pressure increases which, in turn,reflects an increase in liquid volume within fluid collection receptacle1600. Based on the increase of air pressure inside fluid collectionreceptacle 1600, a pressure sensor 1605 may be used to determine acorresponding volume for an amount of pressure within fluid collectionreceptacle 1600. Rigid tube 1610 may be positioned at an approximatemidpoint or center of fluid collection receptacle 1600 to minimizepressure changes caused by the amount of tilt for fluid collectionreceptacle 1600.

As shown in FIG. 16 , pressure sensor 1605 and rigid tube 1610 may be influid communication such that air that is pushed into rigid tube 1610 isalso pushed through port 1635 into pressure sensor 1605. However, an airpermeable liquid proof seal may be implemented to ensure that a liquidwithin rigid tube 1610 cannot come into contact with pressure sensor1605 or other electronics within fluid collection receptacle 1600. Inother words, rigid tube 1610 may be connected to port 1635 throughadapter 1630. Fluid collection receptacle 1600 may further include abreast pump manifold 1615 which may contain electronics, sensors, acomputer processor, antennas, transmitters, provide vacuum suction, andattach to adapter 1630 by an air tight connection. Breast pump manifold1615 may further include removable breast flange 1620 for interfacingwith a breast to stimulate milk production.

Adapter 1630 may be fitted with a valve 1625 which may maintain vacuumpressure within manifold 1615 while also allowing a liquid, such asmilk, to fall through valve 1625 and into bottle 1640. As previouslydiscussed, as the liquid accumulates in bottle 1640 and displaces air inbottle 1640, the liquid will enter into rigid tube 1610. As the liquidrises in tube 1610, air within tube 1610 may be compressed, increasingair pressure within tube 1610. Pressure sensor 1605 may detect thisincreased pressure and provide this information wirelessly or with awired connection, to a processor which may then determine a volume ofliquid within bottle 1640 based on the pressure detected from pressuresensor 1605 and the known volume of bottle 1640. Pressure sensor 1605may be a piezoresistive silicon pressure sensor with a digital output,or may be implemented as another pressure sensor known in the art.

FIG. 17 illustrates an assembled view of the fluid collection receptacle1600 shown in FIG. 16 . Fluid collection receptacle 1700 implements apressure sensor 1705 with a rigid tube 1710 to track pressure changesand determine a volume of fluid within fluid collection receptacle 1700.Pressure sensor 1705 may detect air pressure inside rigid tube 1710,which may be enclosed by fluid within fluid collection receptacle 1700.As liquid fills rigid tube 1710, air pressure increases which, in turn,reflects an increase in liquid volume within fluid collection receptacle1700. Based on the increase of air pressure inside fluid collectionreceptacle 1700, a pressure sensor 1705 may be used to determine acorresponding volume for an amount of pressure within fluid collectionreceptacle 1700. Rigid tube 1710 may be positioned at an approximatemidpoint or center of fluid collection receptacle 1700 to minimizepressure changes caused by the amount of tilt for fluid collectionreceptacle 1700.

As shown in FIG. 17 , pressure sensor 1705 and rigid tube 1710 may be influid communication such that air that is pushed into rigid tube 1710 isalso pushed through port 1735 into pressure sensor 1705. However, an airpermeable liquid proof seal may be implemented to ensure that a liquidwithin rigid tube 1710 cannot come into contact with pressure sensor1705 or other electronics within fluid collection receptacle 1700. Inother words, rigid tube 1710 may be connected to port 1735 throughadapter 1730. Fluid collection receptacle 1600 may further include abreast pump manifold 1715 which may contain electronics, sensors, acomputer processor, antennas, transmitters, provide vacuum suction, andattach to adapter 1730 by an air tight connection. Breast pump manifold1715 may further include removable breast flange 1720 for interfacingwith a breast to stimulate milk production.

Adapter 1730 may be installed on bottle 1740 by mating threads disposedon adapter 1730 and bottle 1740. Adapter 1730 may also attach to a valve1725 which may be disposed in manifold 1715 by mating threads on adapter1730 and an inside of manifold 1715. Adapter 1730 essentially provides aconnection between manifold 1715 and bottle 1740 and a connectionbetween rigid tube 1710 and port 1735 for pressure sensor 1705.

As previously discussed, adapter 1730 may be fitted with a valve 1725.In this configuration, valve 1725 may maintain vacuum pressure withinmanifold 1715 while also allowing a liquid, such as milk, to fallthrough valve 1725 and into bottle 1740. As previously discussed, as theliquid accumulates in bottle 1740 and displaces air in bottle 1740, theliquid will enter into rigid tube 1710. As the liquid rises in tube1710, air within tube 1710 may be compressed, increasing air pressurewithin tube 1710. Pressure sensor 1705 may detect this increasedpressure and provide this information wirelessly or with a wiredconnection, to a processor which may then determine a volume of liquidwithin bottle 1740 based on the pressure detected from pressure sensor1705 and the known volume of bottle 1740. Pressure sensor 1705 may be apiezoresistive silicon pressure sensor with a digital output, or may beimplemented as another pressure sensor known in the art.

FIG. 18 illustrates an exploded view of another embodiment of a fluidcollection receptacle 1800 that implements a pressure sensor 1845 withrigid tubes 1825 and 1830 to track pressure changes and determine avolume of a fluid within fluid collection receptacle 1800. Pressuresensor 1845 may detect air pressure inside rigid tube 1825, which may beenclosed by fluid within fluid collection receptacle 1800. As liquidfills rigid tube 1830, air pressure increases which, in turn, reflectsan increase in liquid volume within fluid collection receptacle 1800.Based on the increase of air pressure inside fluid collection receptacle1800, a pressure sensor 1805 may be used to determine a correspondingvolume for an amount of pressure within fluid collection receptacle1800. Rigid tube 1810 may be positioned at an approximate midpoint orcenter of fluid collection receptacle 1800 to minimize pressure changescaused by the amount of tilt for fluid collection receptacle 1800.

As shown in FIG. 18 , fluid collection receptacle 1800 includes amanifold 1805 which further provides a flange 1810 for interfacing witha breast for stimulating milk production. Vacuum pressure may be appliedvia manifold 1805 and flange 1810 to a nipple to cause the nipple toexpress milk. Fluid collection receptacle 1800 may further include avalve 1815 which maintains vacuum within manifold 1815 while alsoallowing a liquid, such as milk, to pass through valve 1815 into bottle1820. Valve 1815 may connect to bottle 1820 by mating threads or otherfasteners disposed in valve 1815 and bottle 1820. Valve 1815, may alsoconnect to manifold 1805 by a threaded connection or by other fastenersknown in the art.

In FIG. 18 , fluid collection receptacle 1700 provides rigid tube 1830,which may also be referred to as a second rigid tube or an outside rigidtube. Second rigid tube 1830 may include a valve interface 1835 whichmay selectively connect or interface second rigid tube 1830 to valve1815 such that an opening in second rigid tube 1830 may be disposed moreclosely to a bottom of bottle 1820 than a top of bottle 1820. Further,second rigid tube 1830 may be closed on one end and have a greaterdiameter than rigid tube 1825, which is disposed in a bottom of bottle1820. Rigid tube 1825 may be fashioned as integral to bottle 1820 andconnect to port 1840 which provides a connection point and sensor pointfor pressure sensor 1845.

FIG. 19 illustrates an assembled view of the fluid collection receptacle1800 shown in FIG. 18 as fluid collection receptacle 1900. Fluidcollection receptacle 1900 may include a manifold 1905, a flange 1910, avalve 1915, a bottle 1920 with integral rigid tube 1925, a second rigidtube 1930 with a valve interface 1935, a port 1940, and a pressuresensor 1945, each of which are similar in implementation and descriptionto corresponding parts shown in FIG. 18 and discussed above.

A shown in FIG. 19 , manifold 1905 may connect to valve 1915 and alsoconnect, by threaded connection, or other fasteners known in the art, tobottle 1920 such that valve 1915 is disposed on a top of bottle 1920 orwithin manifold 1905. Valve 1915 may further connect to or interfacewith second rigid tube 1935 such that second rigid rube 1935 is securedover and around rigid tube 1925 within bottle 1920. Rigid tube 1925 mayprovide fluid communication between an inside of bottle 1920 and anoutside of bottle 1920 through port 1940 such that pressure sensor 1945may be exposed to pressure changes within bottle 1920.

In operation, as a liquid, such as milk, is received into manifold 1905and falls through valve 1915, the liquid may collect within bottle 1920.As a liquid level rises in bottle 1920 from accumulating liquid, theliquid may enter second rigid tube 1925 and begin to push air into rigidtube 1925. The air may become increasingly pressurized as additionalliquid is received into bottle 1920 and pushes further and further intosecond rigid tube 1925. This increasing pressurization reflects anincrease in liquid volume within fluid collection receptacle 1900. Basedon the increase of air pressure inside fluid collection receptacle 1900,information derived from pressure sensor 1945 may be used to determine acorresponding volume for an amount of pressure within fluid collectionreceptacle 1900.

The foregoing description has been presented for purposes ofillustration. It is not exhaustive and does not limit the invention tothe precise forms or embodiments disclosed. Modifications andadaptations will be apparent to those skilled in the art fromconsideration of the specification and practice of the disclosedembodiments. For example, components described herein may be removed andother components added without departing from the scope or spirit of theembodiments disclosed herein or the appended claims.

Other embodiments will be apparent to those skilled in the art fromconsideration of the specification and practice of the disclosuredisclosed herein. It is intended that the specification and examples beconsidered as exemplary only, with a true scope and spirit of theinvention being indicated by the following claims.

What is claimed is:
 1. A fluid collection receptacle, comprising: acapacitive sensor installed between a base of the fluid collectionreceptacle and a top of the fluid collection receptacle, wherein thecapacitive sensor detects a fluid level of fluid within the fluidcollection receptacle.
 2. The fluid collection receptacle of claim 1,wherein the capacitive sensor is installed on an inside surface of thefluid collection receptacle.
 3. The fluid collection receptacle of claim1, wherein the capacitive sensor is installed within a wall of the fluidcollection receptacle.
 4. The fluid collection receptacle of claim 1,wherein the capacitive sensor is installed on an outside surface of thefluid collection receptacle.
 5. The fluid collection receptacle of claim1, wherein the capacitive sensor includes a conductive trace.
 6. Thefluid collection receptacle of claim 5, wherein the conductive traceconnects a plurality of capacitive elements as part of the capacitivesensor.
 7. The fluid collection receptacle of claim 5, wherein thecapacitive sensor includes a second conductive trace.
 8. The fluidcollection receptacle of claim 7, wherein the second conductive traceconnects a second plurality of capacitive elements as part of thecapacitive sensor.
 9. The fluid collection receptacle of claim 8,wherein a capacitive effect is produced between the first plurality ofcapacitive elements and the second plurality of capacitive elements. 10.The fluid collection receptacle of claim 1, further comprising a basewhich connects to the capacitive sensor.
 11. The fluid collectionreceptacle of claim 10, wherein the base further connects to the fluidcollection receptacle.
 12. The fluid collection receptacle of claim 10,further comprising a processor which identifies a relative amount ofcapacitance from the capacitance sensor and identifies, based on therelative amount of capacitance from the capacitance sensor, a level offluid within the fluid collection receptacle.
 13. A capacitive sensor,comprising: a surface of a fluid collection receptacle, a capacitivesensor installed on or in the surface of the fluid collectionreceptacle, and the capacitive sensor including a first capacitiveelement and a second capacitive element, wherein the capacitive sensordetects a level of fluid within the fluid collection receptacle.
 14. Thecapacitive sensor of claim 13, further comprising a first conductivetrace connected to the first capacitive element and a second conductivetrace conducted to the second capacitive element.
 15. The capacitivesensor of claim 14, wherein the first capacitive element is one of aplurality of first capacitive elements.
 16. The capacitive sensor ofclaim 15, wherein the second capacitive element is one of a plurality ofsecond capacitive elements.
 17. The capacitive sensor of claim 13,wherein a capacitive effect is produced between the first capacitiveelement and the second capacitive element.
 18. The capacitive sensor ofclaim 13, further comprising a base which electrically connects to thefirst capacitive element and the second capacitive element.
 19. Thecapacitive sensor of claim 18, wherein the base further connects to thefluid collection receptacle.
 20. The capacitive sensor of claim 18,further comprising a processor which identifies a relative amount ofcapacitance between the first capacitive element and the secondcapacitive element and identifies, based on the relative amount ofcapacitance between the first capacitive element and the secondcapacitive element, a level of fluid within the collection receptacle.